The present invention relates to a key system for activating a lock device by, for example, performing a mechanical operation with a mechanical key or a wireless communication operation with an electronic key.
Conventional keys for a vehicle include a master mechanical key and a sub-mechanical key (for example, refer to Japanese Laid-Open Patent Publication No. 6-167148). The master mechanical key is mainly used by the vehicle owner. The sub-mechanical key is used when the master mechanical key is not on hand. The conventional master mechanical key may be used to lock and unlock any lock in the vehicle, whereas the use of the sub-mechanical key is conditional. Thus, the sub-mechanical key cannot lock and unlock every lock in the vehicle. For example, the sub-mechanical key cannot lock and unlock a glove compartment in the vehicle. Such conditional use of the sub-mechanical key effectively prevents, for example, a third party from removing valuables from the glove compartment without the vehicle owner's permission.
For example, when using a valet parking service, the vehicle owner carries the master mechanical key and gives the sub-mechanical key to the parking attendant so that the parking attendant can operate the vehicle with the sub-mechanical key. The use of the sub-mechanical key is conditional. That is, the sub-mechanical key cannot lock and unlock the glove compartment. Thus, the parking attendant cannot open the glove compartment or the trunk of the vehicle. In this manner, a sub-mechanical key with such a condition-imposing function effectively improves security and prevents valuables in the glove compartment or the trunk from being stolen.
In recent years, an electronic key system, which does not require the vehicle owner to perform a key operation, may be installed in a vehicle (refer to Japanese Laid-Open Patent Publication No. 2004-025937). The electronic key system performs wireless communication so that when the vehicle transmits a request signal, an electronic key carried by the vehicle owner transmits its ID code in response. The vehicle receives the ID code of the electronic key through wireless communication and determines whether the ID code of the electronic key matches the ID code of the vehicle. When the two ID codes match, the vehicle locks or unlocks its door lock and enables the engine to be started.
If the glove compartment of the vehicle does not have a wirelessly communicable lock unit, the electronic key (portable remote controller) of the vehicle cannot be used to lock and unlock the glove compartment. To lock and unlock the glove compartment, a mechanical key that functions as a master key must be prepared.
When using a valet parking service, the vehicle owner must always carry both the master key and the sub-key so that the parking attendant can use the sub-key. This is inconvenient since the vehicle owner must always carry two keys.
When a sub-key is not provided for an electronic key, the vehicle owner must register a new ID code with the vehicle to prepare a sub-key before using the valet parking service. Accordingly, the vehicle owner must carry a plurality of vehicle keys.